How unit 1 is examined
This unit covers one topic, the phases a software product passes through from idea to retirement. It has not been asked in the supplied papers, so learn the phases in order.
Software product life cycle
<span style="display:inline-block;padding:.16em .6em;border:1.5px solid currentColor;border-radius:999px;font-size:.68em;font-weight:700;letter-spacing:.06em;text-transform:uppercase;opacity:.75">Not asked since 2022</span>
Definition. <mark>The software product life cycle is the sequence of phases a software product goes through from its first idea, through development and release, to maintenance and final retirement.</mark>
Key points.
- Planning and requirements analysis come first: the team decides what the product must do, for whom, and at what cost and schedule.
- Design turns the requirements into architecture, modules, interfaces and data structures.
- Implementation writes the code, and testing checks it against the requirements to find defects.
- Deployment releases the product to users, and maintenance then fixes bugs, adapts it to new environments and adds features.
- Retirement ends the life of the product when maintenance costs exceed its value and it is replaced.
Last-minute revision
- Phases in order: planning, requirements, design, implementation, testing, deployment, maintenance, retirement.
- The life cycle covers the whole life of the product, including maintenance and retirement, not only development.
- Requirements say what the product does; design says how it will be built.
- Testing compares the built product with the requirements.
- Maintenance is usually the longest and costliest phase.
Memory hooks
- "Pretty Rare Designs Include Tested Deployments, Maintained Regularly": Planning, Requirements, Design, Implementation, Testing, Deployment, Maintenance, Retirement.
- Idea to grave: a product is born in planning and dies in retirement.
Coverage checklist
- Software product life cycle: definition and phases covered; no past questions in the supplied papers.